#include<stdio.h>
int sq(int x){return x*x;}
#define SQ(x)  ((x)*(x))
int gcd(int a,int b){return b?gcd(b,a%b):a;}
int main(){
    printf("%d\n",33==gcd(66,99));
    printf("%d\n",2==gcd(6,8));
    printf("%d\n",6==gcd(6,0));
    return 0;
}
